Mix the butter with the sugar, add the egg, and then the flour and baking soda.

Make well and spread 2/3 of the dough in the shape of a tart.

For the stuffing, cut the walnuts into pieces and mix with grated chocolate, cocoa and rum essence.

Place the filling over the dough, and spread the strips of the rest of the dough on top.

Bake for about 30 minutes, until the strips of dough on top are browned.

Remove the cake from the oven, allow it to cool slightly, remove it from the removable form and place it on a kitchen rack for cooling.

Serve with a scoop of Sandra Prestige vanilla ice cream!